CN111868623A

CN111868623A - Image pickup apparatus

Info

Publication number: CN111868623A
Application number: CN201880091326.6A
Authority: CN
Inventors: 中村优太
Original assignee: Nidec Copal Corp
Current assignee: Nidec Copal Corp
Priority date: 2018-03-22
Filing date: 2018-12-21
Publication date: 2020-10-30
Also published as: JP2019168509A; WO2019181122A1

Abstract

The imaging device includes: a substrate on which an imaging unit is mounted; a lens barrel that holds a lens; and an aperture plate located between the lens and the image pickup unit and connected to a heat source.

Description

Image pickup apparatus

Technical Field

One embodiment of the present invention relates to an imaging device and the like.

Background

In an image pickup apparatus, an O-ring or the like is sometimes used for attaching a member such as a lens barrel to a housing for the purpose of water-proofing and dust-proofing in the housing. Such an imaging device is disclosed in, for example, patent document 1.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 8-102881

Disclosure of Invention

Problems to be solved by the invention

An imaging device such as a camera or a digital camera mounted on a smartphone, an automobile, or the like is often used outdoors, and its usage environment is various. For example, when the imaging device is used at a low outside air temperature, the temperature of the lens is lowered by the outside air. At this time, the water vapor inside the housing isolated from the outside air by the O-ring is cooled by the lens, and condensation may occur inside the housing of the lens. When the lens condenses, light from the subject cannot be normally imaged on the image pickup element, which is not preferable. A technique capable of suppressing dew condensation on a lens with a simple structure is required.

Means for solving the problems

The present invention adopts the following means to solve the above problems and the like. In the following description, for the purpose of facilitating understanding of the present invention, reference numerals and the like in the drawings are attached in parentheses, but the respective components of the present invention are not limited to these designated components and should be construed broadly to the extent that those skilled in the art can understand the present invention technically.

One aspect of the present invention is an imaging apparatus including:

a substrate (41) on which an imaging unit (42) is mounted;

a lens barrel (1b) that holds a lens (11); and

and an aperture plate (12) which is positioned between the lens and the image pickup unit and is connected to a heat source.

According to the imaging device having the above configuration, since the heating function can be provided to the aperture plate for determining the outermost position of the light passing therethrough, the configuration of the imaging device can be simplified, and the temperature inside the housing of the lens can be further increased. This makes it possible to suppress the occurrence of condensation on the lens even when the imaging device is used at a low outside air temperature, for example. In other words, condensation on the lens can be suppressed with a simple configuration.

In the above-described image pickup apparatus, it is preferable that,

the aperture plate includes: a plate-shaped part (12b) having a through hole (12a) through which light from an object passes to the imaging part; and an extension portion (12c) extending from the plate-like portion toward the base plate.

According to the imaging device having the above configuration, since the substrate and the plate-like portion can be connected to each other in a simple shape, the manufacturing process of the imaging device can be prevented from being complicated, and the manufacturing cost can be reduced. In addition, power, heat, and the like can be supplied from the substrate to the plate-shaped portion.

In the above-described image pickup apparatus, it is preferable that,

the aperture plate has a through hole through which light from an object passes to the image pickup section,

the imaging device further includes a heater (12d) as the heat source, and the heater (12d) is provided along the periphery of the through hole.

According to the imaging device having the above configuration, since the periphery of the through hole can be directly heated, the periphery of the optical axis of the lens can be efficiently heated. This can effectively suppress scattering due to condensation of light from the object.

In the above-described image pickup apparatus, it is preferable that,

the substrate is provided with an electronic component,

the aperture plate is connected to the electronic component or the imaging unit as the heat source.

According to the imaging device having the above configuration, the lens can be heated by waste heat based on the electric power consumed by the electronic components, and therefore, the energy in the imaging device can be effectively used, and the condensation of the lens can be suppressed.

In the above-described image pickup apparatus, it is preferable that,

the surface of the aperture plate is subjected to a treatment for suppressing reflection of light.

According to the imaging device having the above configuration, for example, stray light or the like due to reflection from the surface of the aperture plate can be suppressed, and therefore, the quality of an image to be captured can be improved.

In the above-described image pickup apparatus, it is preferable that,

the aperture plate has thermal conductivity.

According to the imaging device having the above configuration, since heat from the heat source can be dissipated over the entire aperture plate, the inside of the housing of the lens can be heated satisfactorily.

In the above-described image pickup apparatus, it is preferable that,

the lens barrel holds a 1 st lens (11a) closest to an object side and a 2 nd lens (11b) closest to the object side,

the aperture plate is positioned between the 1 st lens and the 2 nd lens.

According to the imaging device having the above configuration, the 1 st lens which is likely to be affected by the outside air temperature and to cause dew condensation can be efficiently heated, and therefore the occurrence of dew condensation in the 1 st lens can be effectively suppressed.

In the above-described image pickup apparatus, it is preferable that,

the imaging device further includes a waterproof seal (15) disposed between the lens and the lens barrel.

According to the imaging device having the above configuration, since the intrusion of water and water vapor from the outside can be suppressed, the humidity inside the housing can be prevented from increasing. This can maintain a state in which condensation on the lens is unlikely to occur.

Drawings

Fig. 1 is an external perspective view of the imaging device according to the present embodiment.

Fig. 2 is an exploded perspective view of the imaging device of the present embodiment.

Fig. 3 is a sectional view of the imaging device of the present embodiment.

Fig. 4 is a plan view of the heat transfer port plate of the present embodiment.

Detailed Description

One of the features of the imaging device according to the present invention is that the aperture plate is positioned between the lens and the imaging unit and connected to the heat source.

In the present specification, the center position of the lens, that is, the center position of light incident on the imaging element is referred to as the "optical axis". An image pickup object located on the opposite side of the image pickup element with respect to the lens is referred to as an "object". The direction in which the object is located with respect to the image pickup element is referred to as "front side" or "front in the optical axis direction", and the direction in which the image pickup element is located with respect to the object is referred to as "rear side" or "rear in the optical axis direction".

The embodiments of the present invention will be explained based on the following configurations. However, the embodiments described below are merely examples of the present invention, and the technical scope of the present invention is not to be construed in a limiting manner. In the drawings, the same components are denoted by the same reference numerals, and the description thereof may be omitted.

1. Detailed description of the preferred embodiments

2. Supplementary items

< 1. embodiment >

Embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is an external perspective view of the imaging device according to the present embodiment. Fig. 2 is an exploded perspective view of the imaging device of the present embodiment. Fig. 1 and 2 are views viewed from the front side. Fig. 3 is a sectional view of the imaging device of the present embodiment. Fig. 3 shows a cross-sectional view along the cutting line III-III of fig. 1.

The x-axis, y-axis, and z-axis are shown in the figures. An axis parallel to the optical axis of the lens and directed toward an object when viewed from the image pickup element is defined as a "z-axis". An axis perpendicular to the z-axis is defined as the "x-axis". An axis perpendicular to both the z-axis and the x-axis is defined as a "y-axis". Here, the x-axis, y-axis, and z-axis form three-dimensional orthogonal coordinates of the right-handed system. Hereinafter, the direction of the arrow on the z-axis may be referred to as the "z-axis + side", and the direction opposite to the arrow may be referred to as the "z-axis-side", and the same applies to other axes.

As shown in fig. 1 to 3, the image pickup apparatus of the present embodiment includes a front case 1a, a lens barrel 1b, a lens group 11, a heat transfer port plate 12, a 1 st port plate 13, a 2 nd port plate 14, a waterproof seal 15, a substrate 41, and an image pickup element 42. The lens group 11 includes a 1 st lens 11a, a 2 nd lens 11b, a 3 rd lens 11c, and a 4 th lens 11 d.

< front case 1a >

The front case 1a is a member that forms a case (case) of the image pickup apparatus together with a rear case (not shown), and is formed of resin or the like. The front case 1a is connectable to and openable from the rear case at the rear in the optical axis direction, and has a substantially rectangular side surface to cover the optical axis. By coupling the front case 1a and the rear case, a space for accommodating the lens barrel 1b, the substrate 41, the image pickup device 42, and the like is formed. The front case 1a is not limited to the structure coupled to the rear case, and may be coupled to the case, for example.

< lens barrel 1b >

As shown mainly in fig. 3, the lens barrel 1b is a substantially cylindrical member, and includes a large diameter portion 1d, a medium diameter portion 1e, a small diameter portion 1f, and a penetrating portion 1 c. In the image pickup apparatus of the present embodiment, the front housing 1a and the lens barrel 1b are integrally formed. On the inner surface of the lens barrel 1b, a large diameter portion 1d, an intermediate diameter portion 1e, and a small diameter portion 1f are formed so as to be sequentially continuous toward the z-axis + side. The large diameter portion 1d has a cylindrical shape extending in the optical axis direction with the optical axis as the center. The intermediate diameter portion 1e has a diameter smaller than that of the large diameter portion 1d, and has a substantially cylindrical shape extending in the optical axis direction with the optical axis as the center. The small diameter portion 1f has a diameter smaller than that of the medium diameter portion 1e, and has a tapered shape that expands in diameter toward the + side of the z axis.

A stepped portion 1g, which is a boundary between the large diameter portion 1d and the medium diameter portion 1e, is formed on the inner surface of the lens barrel 1 b. A through portion 1c penetrating from the inside of the lens barrel 1b to the outside of the lens barrel 1b is formed at one portion of the outer edge (outer side with respect to the optical axis) of the stepped portion 1 g. The through portion 1c is a gap through which the extending portion 12c is inserted.

The lens barrel 1b holds the 1 st lens 11a, the 2 nd lens 11b, the 3 rd lens 11c, and the 4 th lens 11 d. Specifically, the 2 nd lens 11b, the 1 st aperture plate 13, the 3 rd lens 11c, the 2 nd aperture plate 14, and the 4 th lens 11d are housed inside the intermediate diameter portion 1e so as to be sequentially continuous toward the z-axis + side. Here, the 1 st aperture plate 13 and the 2 nd aperture plate 14 determine the outermost position of the light passing therethrough.

The large diameter portion 1d accommodates the 1 st lens 11 a. An L-shaped groove 11as having an outer diameter smaller than the z-axis side of the 1 st lens 11a is formed on the z-axis + side of the 1 st lens 11 a.

< waterproof seal 15 >

The waterproof seal 15 is disposed between the lens and the lens barrel 1 b. In the present embodiment, the waterproof seal 15 is an annular member formed of an elastic member such as rubber, and is disposed between the 1 st lens 11a and the lens barrel 1b, thereby functioning to couple the 1 st lens 11a and the lens barrel 1b without a gap. Specifically, the waterproof seal 15 is disposed radially outward of the L-shaped groove 11as and radially inward of the large diameter portion 1d of the lens barrel 1b (see fig. 3).

< substrate 41 >

The substrate 41 is a rigid substrate on which electronic components including the imaging element 42 are mounted. The imaging element 42 is a specific example of the "imaging section" according to the present invention. The imaging element 42 is a photoelectric conversion element that converts the irradiated light into an electric signal, and is, for example, a C-MOS sensor, a CCD, or the like, but is not limited thereto. In addition, an imaging unit requiring an imaging function other than the imaging element 42 may be used in the imaging apparatus. The electric signal acquired by the imaging element 42 is subjected to predetermined electric processing or signal processing by the electronic components mounted on the substrate 41, and is then output to the outside of the imaging apparatus as image data.

< Heat conduction aperture plate 12 >

The heat conduction aperture plate 12 is located between the lens and the imaging section. In the present embodiment, the heat conduction aperture plate 12 is located between the 1 st lens 11a closest to the object side and the 2 nd lens 11b second closest to the object side. The heat transfer aperture plate 12 determines the outermost position of the light passing therethrough.

Fig. 4 is a plan view of the heat transfer port plate of the present embodiment. Fig. 4 shows a heat conductive aperture plate before bending. As shown in fig. 4, the heat transfer port plate 12 includes a plate-shaped portion 12b, an extension portion 12c, and a heater 12 d. In the present embodiment, the plate-shaped portion 12b and the extending portion 12c are integrally formed by a member having thermal conductivity. Specifically, it is preferable that the plate-shaped portion 12b and the extension portion 12c are formed of a member having a thermal conductivity of more than 1.0W/m · K, for example, because heat can be sufficiently conducted. More specifically, the plate-shaped portion 12b and the extension portion 12c are integrally formed of, for example, aluminum or a metal such as copper. The plate-shaped portion 12b and the extending portion 12c may be integrally formed by printing a flexible substrate, a high thermal conductive resin, or the like. The plate-like portion 12b is a plate-like member having an annular shape, and the plate-like portion 12b includes a through hole 12a centered on the optical axis, and the through hole 12a allows light from the object to pass through to the imaging element 42.

As shown in fig. 3 and 4, the extension portion 12c is a plate-like member having a rectangular surface and extending from the plate-like portion 12b toward the base plate 41. Specifically, the extending portion 12c has the 1 st end and the 2 nd end connected to a part of the outer edge of the plate-like portion 12 b. In a state before the bending of the heat transfer port plate 12, the extension portion 12c extends toward the y-axis + side. The extending portion 12c is bent at a position a in the vicinity of the plate-shaped portion 12b to form a bent portion 12 e. Thereby, the extending direction of the extending portion 12c is changed from the y-axis + side to the z-axis + side (see fig. 3). The extension portion 12c is inserted through the through portion 1c of the lens barrel 1b provided on the z-axis + side of the 1 st lens 11a and on the z-axis-side of the 2 nd lens 11b in a state of being attached to the imaging apparatus, and is provided outside the lens barrel 1 b. The extending portion 12c extends from the through portion 1c toward the vicinity of the substrate 41 in a direction away from the optical axis on the z-axis + side with respect to the through portion 1c, and is bent so that the extending direction is changed to the y-axis side in the vicinity of the substrate 41, and the 2 nd end is connected to the substrate 41.

As shown in fig. 4, the heat transfer aperture plate 12 is connected to a heat source. In the present embodiment, on the surface of the heat transfer port plate 12, a heater 12d as a heat source is provided along the periphery of the through hole 12 a. Specifically, the heater 12d is an electric heating wire such as a nichrome wire or a ferrochrome wire. The heater 12d may be a sheathed wire. The heater 12d has a 1 st end located on the x-axis-side of the 2 nd end of the extension portion 12c and electrically connected to the substrate 41, and a 2 nd end located on the x-axis + side of the 2 nd end of the extension portion 12c and electrically connected to the substrate 41. The heater 12d includes: a 1 st extending portion 12da extending from the 1 st end toward the plate-like portion 12b along the extending direction of the extending portion 12 c; a surrounding portion 12db connected to the 1 st extending portion 12da and extending along the periphery of the through hole 12 a; and a 2 nd extension 12dc connected to the surrounding portion 12db, extending along an extending direction of the extension 12c and reaching the 2 nd end. A voltage is applied from the substrate 41 to the heater 12d between the 1 st and 2 nd ends. This allows the heater 12d to be heated by current flow, thereby increasing the temperature around the 1 st lens 11 a. Further, the plate-shaped portion 12b and the extension portion 12c having thermal conductivity conduct heat emitted from the heater 12d, and thereby the temperature around the 1 st lens 11a can be increased non-locally (widely).

The surface of the heat transfer aperture plate 12 is subjected to a treatment for suppressing reflection of light. More specifically, the reflectance of visible light can be suppressed to a predetermined value or less by applying surface treatment such as black painting and black registration, coating treatment, or the like to the heat transfer aperture plate 12.

According to the image pickup device having the above configuration, since the heating function can be provided to the heat conduction aperture plate 12 for determining the outermost position of the light passing therethrough, the configuration of the image pickup device can be simplified, and the temperature of the 1 st lens 11a on the inner side of the housing can be further increased. This can suppress the occurrence of condensation on the 1 st lens 11a even when the imaging device is used at a low outside air temperature, for example. In other words, condensation on the lens can be suppressed with a simple configuration.

In the imaging device having the above configuration, the heat transfer aperture plate 12 includes: a plate-like portion 12b having a through hole 12a through which light from the subject passes to the imaging element 42; and an extension portion 12c extending from the plate-like portion 12b toward the base plate 41. This allows the substrate 41 and the plate-like portion 12b to be connected with a simple shape, and thus can prevent the manufacturing process of the imaging device from becoming complicated and reduce the manufacturing cost. In addition, power, heat, and the like can be supplied from the substrate to the plate-shaped portion.

In the imaging device having the above configuration, the heater 12d is provided along the periphery of the through hole 12a and serves as a heat source, and therefore, the periphery of the through hole 12a can be directly heated, and the periphery of the optical axis of the 1 st lens 11a can be efficiently heated. This can effectively suppress scattering due to condensation of light from the object.

In the imaging apparatus according to the present embodiment, since the process of suppressing the reflection of light is performed on the surface of the heat conduction aperture plate 12, for example, stray light or the like based on the reflection from the surface of the heat conduction aperture plate 12 can be suppressed, and thus the quality of the captured image can be improved.

In the imaging apparatus of the present embodiment, since the heat conductive aperture plate 12 has heat conductivity, heat from the heat source can be dissipated over the entire heat conductive aperture plate 12, and thus the case inside of the 1 st lens 11a can be heated favorably.

In the image pickup apparatus of the present embodiment, the lens barrel 1b holds the 1 st lens 11a closest to the object side and the 2 nd lens 11b second closest to the object side, and the heat conduction aperture plate 12 is located between the 1 st lens 11a and the 2 nd lens 11 b. This enables the 1 st lens 11a, which is susceptible to the influence of the outside air temperature and is likely to cause dew condensation, to be efficiently heated, and therefore the occurrence of dew condensation on the 1 st lens 11a can be effectively suppressed.

In the imaging device according to the present embodiment, the waterproof seal 15 is disposed between the 1 st lens 11a and the lens barrel 1b, and therefore, intrusion of water and water vapor from the outside can be suppressed, and therefore, an increase in humidity inside the housing can be prevented. This can maintain a state in which condensation of the 1 st lens 11a is not likely to occur.

< 2. supplementary items >

The embodiments of the present invention have been specifically described above. The above description is merely an explanation of one embodiment, and the scope of the present invention is not limited to the one embodiment, and is to be interpreted broadly as a scope that can be grasped by those skilled in the art.

In the imaging device of the present embodiment, the structure in which the heater 12d is provided along the periphery of the through hole 12a and serves as a heat source has been described, but a structure in which the heat conduction aperture plate 12 is connected to an electronic component serving as a heat source may be employed. Specifically, for example, the 2 nd end of the extension portion 12c of the heat conduction aperture plate 12 is connected to the image pickup element 42 or other electronic components, so that heat generation of the image pickup element 42 or other electronic components is conducted to the extension portion 12 c. Accordingly, the 1 st lens 11a can be heated by waste heat based on the electric power consumed by the image pickup element 42 and other electronic components, and therefore, the energy in the image pickup apparatus can be effectively used, and condensation on the 1 st lens 11a can be suppressed.

In the imaging apparatus according to the present embodiment, the configuration in which the 1 st lens 11a, the 2 nd lens 11b, the 3 rd lens 11c, and the 4 th lens 11d are held by the lens barrel 1b has been described, but the number of lenses held by the lens barrel 1b may be 3 or less or 5 or more.

In the imaging device of the present embodiment, the configuration in which the outer shape of the plate-shaped portion 12b of the heat transfer port plate 12 is circular has been described, but the outer shape of the plate-shaped portion 12b may be a shape other than circular, such as a polygon.

In the imaging device of the present embodiment, the structure in which the heat conduction port plate 12 includes the plate-shaped portion 12b and the extension portion 12c has been described, but a structure in which the heat conduction port plate 12 does not include the extension portion 12c may be adopted. In this case, power or heat is directly supplied to the plate-shaped portion 12 b.

In the imaging device according to the present embodiment, the waterproof seal 15 is disposed between the 1 st lens 11a and the lens barrel 1b, but the waterproof seal 15 may be disposed between a lens other than the 1 st lens 11a, for example, the 2 nd lens 11b, the 3 rd lens 11c, or the 4 th lens 11d, and the lens barrel 1 b.

Industrial applicability

The present invention is suitable for use as an in-vehicle imaging device, a mobile imaging device, and the like.

Description of the reference symbols

1 a: a front housing; 1 b: a lens barrel; 1 c: a through part; 1 d: a large diameter portion; 1 e: a middle diameter part; 1 f: a small diameter part; 1 g: a step portion; 11: a lens group; 11 a: a 1 st lens 11; 11 b: a 2 nd lens 11; 11 c: a 3 rd lens 11; 11 d: a 4 th lens 11; 11 as: an L-shaped groove part 11; 12: a heat transfer aperture plate; 12 a: a through hole; 12 b: a plate-like portion; 12 c: an extension portion; 12 d: a heater; 12 da: 1 st extension part; 12db of: a surrounding portion; 12 dc: a 2 nd extension part; 12 e: a bending part; 13: a 1 st aperture plate; 14: a 2 nd aperture plate; 15: a waterproof seal; 41: a substrate; 42: an image pickup element.

Claims

1. An image pickup apparatus includes:

a substrate on which an imaging unit is mounted;

a lens barrel that holds a lens; and

and an aperture plate located between the lens and the image pickup unit and connected to a heat source.

2. The image pickup apparatus according to claim 1,

the aperture plate includes:

a plate-like portion having a through hole through which light from an object passes to the imaging portion; and

an extension portion extending from the plate-shaped portion toward the base plate.

3. The image pickup apparatus according to claim 1 or 2,

the imaging device further includes a heater as the heat source, the heater being provided along a periphery of the through hole.

4. The image pickup apparatus according to claim 1 or 2,

the substrate is provided with an electronic component,

5. The image pickup apparatus according to any one of claims 1 to 4,

6. The image pickup apparatus according to any one of claims 1 to 5,

the aperture plate has thermal conductivity.

7. The image pickup apparatus according to any one of claims 1 to 6,

the lens barrel holds a 1 st lens closest to an object side and a 2 nd lens closest to the object side,

the aperture plate is positioned between the 1 st lens and the 2 nd lens.

8. The image pickup apparatus according to any one of claims 1 to 7,

The image pickup apparatus further has a waterproof seal member disposed between the lens and the lens barrel.